Full-Stack Developer

We are looking for a Full Stack Developer with hands-on experience integrating with ERP systems. You will build and maintain integrations that allow businesses to submit invoices to FIRS directly from their existing ERP workflows and extend our platform's capabilities across the stack.

You'll work across our NestJS backend and Next.js frontend, building connectors, APIs, and UI features that make FIRS e-invoicing seamless for businesses already running enterprise software.

What You'll Do

ERP Integration Development

• Design and build integration connectors for ERPs (Microsoft Dynamics, Odoo etc)
• Develop middleware that syncs invoices, credit notes, and payment data between ERP systems and our platform
• Map ERP invoice data models to FIRS UBL 2.1 format (our existing UBL generator handles the final transformation)
• Build webhook receivers for real-time ERP event triggers (invoice posted, payment recorded)
• Handle data mapping edge cases: multi-currency, partial payments, tax code translation, unit of measure conversion

Backend Development (NestJS)

• Extend our REST API with new endpoints for ERP integration workflows
• Build queue-based processing for bulk ERP invoice sync using BullMQ
• Implement retry logic and error handling for unreliable ERP API connections
• Write integration with the FIRS MBS API (validate, sign, transmit invoices)
• Maintain and extend TypeORM entities and database migrations (PostgreSQL)
• Build audit logging for all ERP sync operations

Frontend Development (Next.js)

• Build ERP integration configuration UI (connection setup, field mapping, sync status)
• Create dashboards showing sync status, errors, and processing history
• Extend existing document management pages with ERP-sourced data indicators
• Implement real-time progress indicators for bulk sync operations

API & Platform

• Design APIs that external ERP plugins/extensions can consume
• Write comprehensive API documentation for ERP vendors building their own integrations
• Build and maintain sandbox environments for integration testing
• Support third-party developers integrating with our API

What We're Looking For

Required

• 3+ years of full stack development experience with TypeScript
• Production experience with NestJS or similar Node.js backend frameworks (Express, Fastify)
• Production experience with React (Next.js preferred)
• Hands-on experience integrating with ERP APIs (Business Central OData/REST APIs or Finance & Operations Data Entities)
• Strong understanding of REST API design, authentication (OAuth2, API keys), and webhook patterns
• Experience with PostgreSQL or similar relational databases
• Experience with Redis for caching or message queuing
• Understanding of data mapping between different system schemas (ERP to standardized formats)
• Comfortable working with external API documentation and debugging HTTP integrations

Strongly Preferred

• Experience with Microsoft Azure AD / Entra ID authentication and the Microsoft Graph API ecosystem
• Familiarity with Dynamics 365 Business Central AL extensions or custom connectors
• Experience with BullMQ, RabbitMQ, or similar job queue systems
• Experience with TypeORM or similar ORMs
• Understanding of accounting/invoicing data models (chart of accounts, tax codes, payment terms, document types)
• Experience building multi-tenant SaaS applications
• Familiarity with UBL (Universal Business Language) or similar e-invoicing standards

Nice to Have

• Experience integrating with other ERP systems: SAP Business One, Sage, Odoo, QuickBooks, Xero
• Familiarity with the FIRS e-invoicing system or Nigerian tax compliance
• Experience with Docker, CI/CD pipelines, and cloud deployments (AWS preferred)
• Knowledge of cryptographic operations (AES encryption, RSA signing, certificate handling)
• Contributions to open-source ERP connectors or integration frameworks
• Experience with Power Automate or Azure Logic Apps for low-code ERP integration flows

Our Tech Stack

Why Join Us

• Real impact — You're building infrastructure that every Nigerian business will use. The FIRS mandate makes this a national-scale product.
• ERP integration is the moat — Businesses live in their ERP. The team that nails ERP-to-FIRS integration wins this market.
• Greenfield architecture — You'll design the integration layer from scratch. No legacy code to fight.
• Full stack ownership — Backend APIs, frontend UI, queue workers, external API integrations. You own it end to end.
• Small team, big leverage — Your work directly impacts product capabilities and revenue.

Compensation

• Competitive salary (based on experience)
• Performance bonuses tied to integration milestones
• Equity/stock options (for exceptional candidates)
• Learning budget for certifications (Microsoft, AWS)
• Flexible working arrangement (hybrid/remote)